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Re: 4 GCC regressions, 2 new, with your patch on 2002-07-18T09:56:17Z.


> >    c) I hope to move the code motion to hoist* functions I've
> >       contributed that uses liveness information to validate motion to
> >       given point.  In case we will be systematically choosing points
> >       where flags are alive, we will disable all motion of instructions
> >       having clobbers in parallel
> 
> This will be better.  I hope that in the long run all of GCSE will go
> away and be replaced with a SSA-based pass.

Really? I thought that the SSA on lowlevel RTL is no-no becuase of
subregs and strict low parts etc.  We need some CSE-like pass to cleanup
after last code lowering stage in any stage and it should be global.
> 
> >  3) The clobbers of the instruction I move over are not causing problems
> >     here as the instruction is known to have only one effect of storing
> >     newly created pseudo.
> 
> Then single_set is unnecessary, correct?  You can use PATTERN instead.
I am reffring to instruction I am moving, not the instruction I am
examining.

Honza


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